Method and apparatus for use in forming foundations



April 18, 1967 J. J. BARDGETTE 3,314,240

METHOD AND APPARATUS FOR USE IN FORMING FOUNDATIONS Filed Dec. 21, 1964 5 Sheets-Sheet 2 will IIIHM;

INVENTOR.

0H J. BARGETTE, Flc-3.2. FIG. 5. BY j v ATTORNEY.

April 1s, 1967 Filed Dec. 2l, 1964 Xfl lr l :In

J. J. BARDGETTE METHOD AND APPARATUS FOR USE 1N FORMING FoUNDATIoNs MMU ATTORNEY.

United States Patent 3,314,240 METHOD AND APPARATUS FOR USE IN FORMING FOUNDATIONS .lohn Il. Bardgette, New Orleans, La., assignor, by mesne assignments, to Esso Production Research Company,

Houston, Tex., a corporation of Delaware Filed Dec. 21, 1964, Ser. No. 420,070 Claims. (Cl. 61-53.5)

The present invention generally concerns the construction of drilling platforms and, in particular, it concerns an improved method for forming foundations for drilling pl-atforms. The invention also concerns apparatus for use in driving piles in accordance with this method.

When driving piles by ordinary hammer means, especially piles used to support offshore drilling structures, adequate pile penetrations cannot be achieved in dense sands because of the great buildup of end bearing on the piles in the sand formation. Pile driving in such sands often results in premature refusal, particularly for tension or holddown requirements.

The pile driving method to be described herein overcomes disadvantages inherent in ordinary pile driving techniques. It achieves deep penetrations of pile into dense sand formations with a minimum of pile driving difficulty.

In application Ser. No. 352,923, tiled Mar. 18, 1964, by Arthur L. Guy, entitled, Method and Apparatus for Driving Piles, now Patent No. 3,289,420, an operation is described in which pilings such as steel tubings or cylinders are driven with a hammer in a conventional way while simultaneously jetting water into the sand utilizing a close, hydrostatic system. In the practice of the Guy operation, the resistance to pile penetration is reduced and it is possible to drive the pile through dense, thick sand strata. However, pumping of water in accordance with the Guy technique cannot be resumed when a new section of pile is added until the weld between the new and driven pile sections is adequate to hold the pressure applied by pumping. Welding each new pile section to the previously driven pile sections in this manner consumes much time, especially when welding heavy wall, large ldiameter steel pipes such as those commonly used to support offshore drilling structures and when pumping of water is halted for a prolonged period of time, it is often diiicult or irnpossible to resume movement of the pile.

The present invention permits the pumping of water while the new and driven sections of pile are being welded by securing a packer and holddown assembly to the pile driving head to seal off pumped water from the area of welding.

The method for driving piles, according to the present invention, uses a driving head secured to the upper end of the new pile section to be driven and containing a chamber, a tubular member extending from the chamber through the new pile section to be added and into a driven section of piling, an inflatable packer arranged on the tubular member and located within the driven section of piling, and means extending from the driving head through the tubular member to the interior of the inflatable packer adapted to supply packer-innate fluid to the packer and comprises the steps of pumping fluid through said uid supply means and into said packer to inflate said packer and seal off the annulus between said tubular member and the wall of the driven pile section; and welding the lower end of the new section of pile to the upper end ofthe driven pile section while pumping fluid into said chamber and through said tubular member into said pile.

A primary object of the invention, therefore, is to provide an improved technique for driving piles.

The above and other objects and advantages of the invention will be apparent from the following, more detailed 3,314,240 Patented Apr. 18, 1957 rice description of the invention when taken with the drawings in which:

FIG. l is a side elevation of apparatus embodying the invention and illustrating one manner of driving piles in offshore locations;

FIGS. 2 to 4 are side elevations of a pile to be driven into the underlying sand and illustrating positioning of a jet assembly and its action within the pile in accordance with the method of the Guy application;

FIGS. 5 and 5A are side elevations, partly in section, of the packer apparatus and holddown assembly arranged in the driving head, new pile section and driven pile section in accordance with the invention;

FIG. 6 is a view taken along lines 6-6 of FIG. 5A; and

FIG. 7 is a side elevation of the packer apparatus and holddown assembly arranged in the driven pile section with the packer apparatus in inated condition.

Referring to the drawings in more detail, in FIG. l is shown a barge 10 on which is mounted a platform 11 and a crane 12 from which is suspended a steam hammer 13 used to drive piles 14 into the dense sand formation 15. A zone of less dense sand or mud 16 is located above formation 15 and below water 17. One pile has been driven through to the desired depth or to refusal and the other pile consisting of initial pile sections 14a and a new pile section 14b -are being driven into sand formation 15 by means of a driving head 18 on which is mounted steam hammer 13. The sections of pile are welded together and to driving head 18 as indicated at 19.

FIGS. 2 to 4 show pile section 14a prior to its penetration into sand formation 15. In FIG. 3 a jet line assembly 20 is shown arranged in pile section 14a. Assembly 20 includes a hollow, tubular jet line .member 21, provided with a connection 22 to which a hose 22a is attached at its upper end and which contains perforations 23 adjacent its lower end. Centralizers 24 are arranged along its length to maintain tube 21 upright and centrally positioned within pile section 14a. Cable loops 25 are provided adjacent the upper end of tube 21 to aid in placing it within and removing it from pile section 14. Hose 22a feeds water to tube 21 from an external surface source of supply. The water jets through perforations 23 and aids in washing assembly 20 through mud 16 (see FIG. 3). Once assembly 20 reaches sand formation 15, hose 22a is removed from connection 22 as illustrated in FIG. 4. This ligure also shows the lower end of new pile section 14b welded to the top of pile section 14a. Tube 21 penetrates formation 15 as water Within the pile sections 14 passes into opening 22 through tube 21 and jets from perforations 23.

As shown in FIGS. 5, 5A, 6, and 7, driving head 18, including the anvil portion 31 thereof, is welded to the new section of pile 14b and to a packer and holddown assembly 35. Water fill up lines 32 and an air line 33 are connected .to a chamber in the interior of driving head 18 to supply water and/ or air to the driving head. The upper end of the chamber is closed by means of a plate 34 below the anvil portion 31 thereof. Assembly 35 is arranged in the lower end of driving head 18 and extends through pile 14b into pile 14a. It includes a seal plate 36 welded to the interior of driving head 18. Reinforcing plates or ribs 37 are welded to plate 36 and to a tubular member or pipe 38 which protrudes through and is welded to plate 36 at its upper end and is latched to a pin or lug 40 welded to the interior of pile 14a at its lower end by means of the slot 41 formed thereon. An inflatable packer 42, which includes an expansible sleeve member 43 preferably pleated or ribbed and upper and lower clamps 44 to fasten the sleeve member to tubular member 38, is located within driven pile 14a. A centralizer 45 is also located on tubular member 38 below packer 3 42. A small, hydraulic line 46 is located within tubular member 38. It connects the interior of sleeve member 43 to an outside source of fluid pressure through hose 47, valve 48, and hose 49.

Referring particularly to FIGS. l to 4, the initial section of pile 14a is welded to driving head 18 and then,

pile section 14a is driven down to the hard, dense sand formation 15 by means of steam hammer 13. When pile 14a reaches refusal in sands 15, the pile driving hammer 13 is removed from anvil head 31. The weld connection between head 18 and pile section 14a is severed and jet line assembly 20 with hose 22 connected to it is inserted in the top of pile section 14a and washed down to the tip of this pile by pumping water through hose 22a. After- Wards, hose 22a is removed from its attachment to openings 22. Jet line 21 is positioned open-ended within pile section 14a in this manner.

Then driving head 18 (and the anvil portion 31, thereof) with assembly 35 attached to it is welded to the upper end of a new pile section 1417. Assembly 35 extends through the lower end of pile section 14b. Crane 12, then, picks up and carries the welded driving head and assembly 35 and pile section 14b to the top of pile section 14a where assembly 35 is inserted in pile section 14a and manipulated until slot 41 on tubular member 38 is latched or secured to lug 40 formed on driven pile 14a (see FIGS. and 5A).

Valve 48 is opened and fluid is pumped through hoses 47 and 49 and small diameter pipe 46 to the interior of packer 4sleeve element 43 to inflate and expand the packer element and seal off the annulus between tubular member 38 and pile section 14a below the uppermost end thereof as illustrated in FIG. 7. Water is then pumped into driving head 18 through ll up lines 32 and through tubular member 38 into driven pile section 14a to below inflated packer assembly 42 and below the unwelded corinection 50 between pile sections 14a and 14b. The upper end of pile section 14a is then Welded to the lower end of pile section 14h while water is being pumped. A large, hydrostatic pressure is exerted on the underlying sand formation by means of this closed, hydraulic system. Water llows into the jet line assembly opening 22 and down through jet line 21 into formation 15 at the tip of the pile (see FIG. 4) during the welding operation which may take considerable time.

Once the welding operation connecting pile sections 14a and 14h has been completed, pumping of lluid into driving head 18 is discontinued and fluid pressure within packer sleeve element 42 is released by opening valve 48 which permits the packer to deflate, at least suiciently to carry on pile driving operations and for subsequent movement or manipulation of the packer assembly without causing damage to it.

Then, llup lines 32 and air connection line 33 are used to pump water and air into driving head 18. The water lls the pile sections to a desired level. An air space is left in driving head 18 and also, if needed, in a portion of pile section 14b. As formation 15 at the top of pile section 14a again begins to take water by flow through jet line 21, driving with steam hammer 13 through driving head 18 of the piling is commenced. Resistance to driving of the pile is reduced by the jetting action of the water through the jet line assembly 21 which permits additional penetration by the pile. The column of air remains trapped so that the energy of driving is expended to the wall of the pile and not against the water column inside the pile. Air supply connection 33 may be used to replenish the air supply in driving head 18 in the event air is lost or dissipated through the water.

Additional sections (af-.pile are added to achieve the desired -pile penetrazn.4 The same sequence of steps that was described for adding pile section 14b to pile section 14a would be employed. Thus, to add a new pile section, driving head 18 is removed by severing its connection to the last section of pile added. Then the new pile section with another driving head 18 and another packer and holddown assembly 35 connected by welding is picked up by the crane. Assembly 35 is inserted in the driven pile section and latched to it through slot 41 and lug 40. Packer 42 is inflated and iluid is pumped into the pile below the packer through tubular member 38 and water is jetted into the sand formation while the driven pile section is welded to the new pile section. Then, the packer is deflated and pile sections are driven into the sand formation by the driving head while hydraulic fluid is pumped into the interior of driving head 18 to jet lluid into the sand while driving the pile.

Having fully described the nature, method, objects and advantages of ymy invention, I claim:

1. In a method for driving piles into earth formations using a driving head containing a chamber and provided with a packer and holddown assembly, said packer and holddown assembly comprising a tubular member welded to said driving head and iluidly communicating with said chamber, an inflatable packer surrounding said tubular member adapted to seal oil, when intlated, the annulus between said tubular member and a pile section in which said packer is located, means for supplying fluid to said packer for inating said packer, and means on said tubular member and means on each pile section cooperating to latch together and hold said assembly in position, the steps of:

positioning a jet line assembly comprising a tube provided Iwith an opening at its upper end and perforations at its lower end in the top of a driven pile section and washing said assembly down to the lower end of said pile with fluid;

attaching said driving head to the top of a new pile section to be added to said driven pile sections with said tubular member extending through the lower end of said new pile section;

arranging said new pile section on the uppermost driven pile section with said tubular member and packer mounted thereon extending into said uppermost driven pile section;

latching said tubular member to said uppermost driven pile section;

inflating said packer and sealing olf the annulus between said tubular member and the wall of said uppermost driven pile section;

pumping fluid into said chamber and through said tubular member into said pile sections;

welding said new pile section to said uppermost driven pile section while pumping iluid into said pile sections through said chamber and said tubular member; i discontinuing pumping of water into said pile sections; deating said packer; and

then, driving said piling into said earth formations with said driving head while pumping lluid into said chamber and through said tubular member and through said jet line assembly into said formations.

2. A method as recited in claim 1 in which additional new pile sections are added when necessary by the steps` of:

discontinuing pumping of fluid into said pile sections:

and driving of said piling;

disconnecting said driving head from the uppermost of said driven pile sections;

atta-ching a new pile section to said driving head with said tubular member and packer extending through the lower end of said new pile section; arranging said new pile section on said uppermost driven pile section with said tubular member and packer extending into said uppermost driven pile section;

latching said tubular member to said uppermost driven pile section;

inilating said packer and sealing off the annulus between said tubular member and the wall of said uppermost driven pile section; and

Welding said new pile section to said uppermost driven pile section while pumping iluid into said pile sections through said chamber and said tubular member.

3. In a method for driving piles into earth formations using a driving head containing a chamber and provided with a packer and holddown assembly, said packer and holddown assembly comprising a tubular member welded to said driving head and fludly communicating with said chamber, an inatable packer surrounding said tubular member adapted to seal 01T, when inated, the annulus between said tubular member and a pile section in which said packer is located, means for supplying fluid to said packer for inating said packer, and means on said tubular member and means on each pile section cooperating to latch together and hold said assembly in position, the steps of:

attaching said driving head to the top of a new pile section to be added to said driven pile sections with said tubular member extending through the lower end of said new pile section;

arranging said new pile section on the uppermost driven pile section with said tubular member and packer mounted thereon extending into said uppermost driven pile section;

latching said tubular member to said uppermost driven pile section;

inating said packer and sealing olf the annulus between said tubular member and the wall of said uppermost driven pile section;

pumping uid into said chamber and through said tubular member into said pile sections;

welding said new pile section to said uppermost driven pile section while pumping fluid into said pile sections through said chamber and said tubular member;

discontinuing pumping of water into said pile sections;

deating said packer; and

then, driving said piling into said earth formations with said driving head while pumping uid into said charnber and through said tubular member and into said formations.

4. A method as recited in claim 3 in which additional new pile sections are added when necessary by the steps of:

discontinuing pumping of fluid into said pile sections and driving of said piling;

disconnecting said `driving head from the uppermost of said driven pile sections; and

repeating the steps of attaching vsaid new pile section to said driving head, arranging said new pile section on said uppermost driven pile section, latching said tubular member to said uppermost driven pile section, inflating said packer, and welding the new and driven pile sections together.

5. Apparatus for use in -driving piles comprising:

a driving head having a chamber and fluid inlets to said chamber;

a tubular member secured to said driving head and adapted to extend from the lower end of vsaid chamber, through a section of piling to be driven and into a section of driven piling;

an inflatable packervelement arranged on said tubular member and adapted to be positioned in said driven section of piling; conduit extending from said driving head through said tubular member to said inatable element adapted to carry packer iniiate fluid from an external supply source to the interior of sai-d inatable element; and means on said tubular member and means on said driven pile section cooperating to connect said tubular member to said driven pile section to hold said tubular member in position.

References Cited by the Examiner UNITED STATES PATENTS 911,971 2/1909 Gilbreth 61-53.74 955,729 4/19'10 Welsh 61-53.74 3,215,201 11/1965 Lacy et al 175-67 X CHARLES E. OCONNELL, Primary Examiner.

JACOB SHAPIRO, Examiner. 

5. APPARATUS FOR USE IN DRIVING PILES COMPRISING: A DRIVING HEAD HAVING A CHAMBER AND FLUID INLETS TO SAID CHAMBER; A TUBULAR MEMBER SECURED TO SAID DRIVING HEAD AND ADAPTED TO EXTEND FROM THE LOWER END OF SAID CHAMBER, THROUGH A SECTION OF PILING TO BE DRIVEN AND INTO A SECTION OF DRIVEN PILING; AN INFLATABLE PACKER ELEMENT ARRANGED ON SAID TUBULAR MEMBER AND ADAPTED TO BE POSITIONED IN SAID DRIVEN SECTION OF PILING; 